For those of us in positions to be tweeting on behalf of brands or clients, or advising others on how best to use Twitter as part of the bigger communications picture, let's try to avoid learning the hard way.

The gist: Rep. Anthony Weiner (D-N.Y.) tweeted photos of his privates and then claimed his account had been hacked. Upon investigation, his claim turned out to be false, and he resigned from office.

The lesson: If it's digital media, it's not private. Emails, photos, texts, videos—they're all easy to post and even easier to share. Assume that if it leaves your device, it's not private. If it does leak, you'd better be prepared to come clean. If you don't share inappropriate things in the first place, you won't feel like you have to lie and backtrack to cover up your poor judgment.

The gist: An employee at New Media Strategies accidentally tweeted from the @ChryslerAutos account: “I find it ironic that Detroit is known as the #motorcity and yet no one here knows how to f*cking drive,” bashing the Motor City amid a Detroit-centric new marketing campaign. (That’s our asterisk, not his.) He lost his job, and the agency lost the account.

The lesson: If you manage multiple accounts—some personal and some professional—be absolutely sure you're posting from the right one. With mobile apps and dashboards, it can be easy to mix up accounts. Anything you post can wait an extra minute to ensure it originates from the right place.

The gist: The retailer’s Twitter account posted: “Millions are in uproar in #Cairo. Rumor is they heard our new spring collection is now available online.” The tweet carried a trending hashtag about the revolution in Cairo—presumably to sell clothes. Word of the tasteless promotional tactic quickly spread online, and Internet users, particularly those on Twitter, attacked the brand.

The lesson: Finding a timely news hook for your promotional efforts is OK, but don't hijack a serious topic—such as a revolution in which people are losing their lives—with your unrelated marketing. There's a fine line between witty and tasteless; don't cross it by trying to make your brand relevant at any opportunity.

The gist: The voice of the Aflac duck lost his job after posting jokes about the Japan tsunami on Twitter. Ironically, Aflac reported massive earnings from that particular disaster.

The lesson: Understand your employer's and client's business. Even when posting to a personal account, anything you say can ultimately represent the company for which you work. Making jokes about natural disasters should be an obvious no-no, but even in more gray areas, think about how your comments could impact the people signing your paycheck.

The gist: Just as Australia’s largest airline Qantas was forced to ground its planes, the company began a poorly timed Twitter contest asking fliers to share their “dream luxury in-flight experience.” The hashtag was hijacked with angry tweets.

The lesson: Timing matters. A social media campaign can't live in a vacuum; it has to be part of a bigger business strategy. If that business is going down the drain, think carefully about the implications of any marketing effort.

The gist: Bob Parsons, CEO of GoDaddy.com, shared a video of himself shooting an elephant in Africa. Despite his efforts to quash the sport-hunting rumors and paint the shooting as a good deed to protect farmers' crops, the company lost plenty of customers to a boycott and competitors offering transfer deals with donations to elephant charities.

The lesson: Violence will never make you look good. A rich CEO shooting an elephant on an African safari—no matter his intention—is nothing to be posting on a company blog. He should have known better, especially in the Digital Age.

The gist: Netflix abruptly announced that it would change its business model, separating its DVD rental service as a separate company called Qwikster. In addition to poorly communicating the announcement to customers, Netflix forgot to obtain the Twitter handle of the company, which belonged to a foul-mouthed stoner. Even though Netflix killed the Qwikster spin-off, the company still lost more than 800,000 customers in just a few months.

The lesson: Protect your brand. Your name, your logo, your tagline, these things must be protected to maintain the integrity of what your marketing works so hard to achieve. Make sure you do your research on how your brand name will be used across the Internet, and take all steps necessary to ensure you know who will be speaking from the brand voice.

On the list: “Kutcher has Paterno's back”

The gist: After reading a TV headline (and only the headline), Ashton Kutcher tweeted in support of Joe Paterno after he was fired from his position as head football coach at Penn State. He only later learned about the alleged child sex scandal, but it was too late for just an apology. His PR team took control of his Twitter account.

The lesson: Think before you tweet. It's easy to get caught up in the moment and share thoughts without having all the facts. When you have a large audience, be mindful of how many people you're sharing your opinions with, and understand the implications of what you're saying.

On the list: “Micky's big mouth”

The gist: Miami Heat owner Micky Arison disobeyed the NBA's ban on publicly discussing the lockout, tweeting about it and discussing it with other Twitter users. His fine was five times that of others who were punished for public commentary.

The lesson: Don't break the law. Blatantly ignoring the rules puts you, your client, or your company directly in the path of problems.

The gist: Pasta sauce brand Ragu created a campaign with videos of moms talking about their husbands struggling in the kitchen. Then, they pitched the campaign to dad bloggers, who didn't react in the way the parent-blogger-influencer outreach plan had forecast. Many promptly berated the company for disrespecting dads.

The lesson: Know the people you're pitching. It will always be worth it to think about your content and your message, and do your research on your pitch list before sending a single message. Understand the people you're trying to connect with and be sure your message is the right one to send to them.